<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
        
    </style>
</head>
<body>
    
</body>
<script>
    
    // console.log(Object.prototype.toString)
    // console.log({}.toString())

    // const info = 123;
    // info.toString()

    console.log( Object.prototype.toString.call(123) === "[object Number]");
    console.log( Object.prototype.toString.call("hello") );
    console.log( Object.prototype.toString.call(true) );
    console.log( Object.prototype.toString.call(undefined) );
    console.log( Object.prototype.toString.call(null) );
    console.log( Object.prototype.toString.call({}) );
    console.log( Object.prototype.toString.call([]) );
    console.log( Object.prototype.toString.call(NaN) );
    console.log( Object.prototype.toString.call(function(){}) );
    console.log( Object.prototype.toString.call(Symbol()) );
    console.log( Object.prototype.toString.call(new Date()) );
    console.log( Object.prototype.toString.call(/a/) );




</script>
</html>